1. Field of the Invention
The invention relates to a securing device for the safety belt of a restraining system for motor vehicles, especially for a passive restraining system, wherein one end of the belt is slideable in a slider track, preferably arranged above the vehicle door, and can be locked at the end of the track behind a securing element, movable against a spring force, which securing element extends into the slider track and can be locked by an inertial mass type sensor.
2. Description of the Prior Art
In a known passive-restraining belt system a slider track in the form of a rail is arranged above the door of a vehicle. The track has a vertical section at the center post of the vehicle. The belt which is attached to a stiff end-part can slide along this slider track. In this manner one obtains a movable shoulder point of the belt, and thereby greater ease in entering a car with a restraining system of this type. The mentioned end-part can be moved in a direction toward the front side of the vehicle to permit the person using the safety device to enter the car, while in the safety position, the end-part is secured with respect to pull-forces in the vertical section of the slider track. A locking hook is provided for the actual locking of the mentioned end-part. The locking hook extends into the slider track, and is movable against a spring force by the end-part itself, thereby disposing the end part behind said hook. At the occurrence of tilting forces which exceed a predetermined measure, this hook is locked indirectly by a mass sensor through a force-transmitting lever which is arranged between the mass sensor and the hook, so that the belt cannot move out of the safety position along the slider track. The functional reliability of such a system can be reduced or clearly endangered, if the acceleration of the inertial mass element of the sensor is not sufficient to move the transmitting lever into the lock position, especially when the bearing condition of the transmitting lever has changed, for example, by collected dirt, wear, or the like.